Add site_group filter everywhere region is set

[ryanmerolle]

NetBox version

v3.1.10

Feature type

Change to existing functionality

Proposed functionality

Anywhere region currently exists as a filter, site group should exist as an option.

Use case

Let's say I want to filter racks in datacenters, I cannot do that today.

Database changes

N/A

External dependencies

N/A

[minitriga]

I could only find the filter not applied to racks and rack reservation filters. I have added them. Let me know if i'm missing any others.